An eight-year-old girl was seen in January 1995 for the evaluation of a deformity of the left shoulder, which was occasionally painful at night and during cold weather. Two years earlier, she had been injured while riding as a passenger in the backseat of an automobile that was broadsided by another vehicle; she was not wearing a seat belt at the time of the accident. She sustained an injury of the left shoulder and a minor injury of the head; medical evaluation revealed a fracture of the left clavicle and a small extradural hematoma without a fracture of the skull. She was observed as an inpatient for three days and was discharged with the left arm in a sling. During the following year she was evaluated by two orthopaedic surgeons, who recommended physical therapy.
Our examination revealed a fixed winging deformity of the left scapula, with a palpable mass along the anterosuperior aspect of that bone. The entire clavicle was palpable from the sternoclavicular joint to the acromion, without tenderness. Abduction of the shoulder was limited to 150 degrees on the left compared with 180 degrees on the right. The ranges of flexion, internal rotation, and external rotation were symmetrical. The fixed winging of the left scapula, as viewed from behind the patient, did not change throughout the range of motion of the shoulder. Motor, sensory, and spinal examinations revealed normal findings.
A review of the radiographs that had been made at the time of the original injury revealed a segmental fracture of the clavicle, consisting of a greenstick fracture of the middle third of the clavicle and a physeal separation at the distal portion of the clavicle. The distal fragment was angulated posteriorly, and a large gap was evident between the proximal fragment and the acromion (Fig. 1). Serial follow-up radiographs demonstrated that the distal portion of the clavicle had reconstituted secondary to new-bone formation and that the segmental fragment had fused to the anterosuperior margin of the scapula (Figs. 2, 3-A, and 3-B). This finding was confirmed on a three-dimensional computed tomographic scan (Fig. 4). A diagnosis of cleidoscapular synostosis was made.
Operative excision of the synostosis was performed to relieve the intermittent pain and to correct the fixed deformity. At the time of operative treatment, a superior incision was made in line with the proximal part of the clavicle and was then curved posteriorly along the osseous mass toward the scapula. Extraperiosteal dissection was then performed. There was a solid bridge of bone between the middle of the shaft of the clavicle and the anterosuperior surface of the scapular spine, with complete osseous union at both ends of the synostosis. The synostosis was removed after an osteotomy was performed at the anterior surface of the scapular spine and at the posterior margin of the clavicle. The fragment measured four centimeters in length and 0.9 centimeter in diameter. The surrounding soft tissue filled the space created by the excision; no interpositional material was used. At the two-year follow-up examination, the patient was asymptomatic and had a full and symmetrical range of motion of both shoulders. The scapular winging on the left side had completely resolved, and radiographs demonstrated no evidence of recurrence of the synostosis (Fig. 5).